Canadian Journal of Earth Sciences

The paleomagnetism and U—Th dating of three Canadian speleothems: Ford, and , G. Pearce Canadian Journal of Earth Sciences, , 19 These cave deposits do not appear to show the kind of depositional effects on the recorded magnetic signal as is often the case with sediments. In addition the signal may be referred directly to geographic coordinates so that virtual geomagnetic pole plots may be constructed. This in turn has allowed assessment of any possible bias of the paleofield.

Uranium–thorium dating

Dating[ edit ] Nearly caves have now been discovered in France and Spain that contain art from prehistoric times. Initially, the age of the paintings had been a contentious issue, since methods like radiocarbon dating can produce misleading results if contaminated by samples of older or newer material, [6] and caves and rocky overhangs where parietal art is found are typically littered with debris from many time periods.

But subsequent technology has made it possible to date the paintings by sampling the pigment itself, torch marks on the walls, [7] or the formation of carbonate deposits on top of the paintings. It has been dated using the uranium-thorium method [8] to older than 64, years and was made by a Neanderthal. The radiocarbon dates from these samples show that there were two periods of creation in Chauvet:

Carbonate speleothems that contain ppb-ppm levels of uranium can be dated by the U U Th and U Pa disequilibrium techniques. Accurate ages are possible if the initial concentrations of Th and Pa are well constrained and if the system has remained closed to post-depositional exchange of uranium, thorium, and protactinium.

Bosna i Hercegovina From the book “Politics of Genocide” author dr. Herman During the civil wars that accompanied the dismantling of the Federal Republic of Yugoslavia in the s, the United States, Germany, NATO, and the European Union EU all sided with the national groups seeking to break away from the unified federal state, and opposed the national group that held out for the longest time to preserve it, the Serbs; this placed the Western bloc solidly behind the Croats and Slovenes, then the Bosnian Muslims, and finally the Kosovo Albanians.

Because the wars were supported and even carried out by the NATO powers, and there was significant ethnic cleansing and ethnic killings, it goes almost without saying that not only “ethnic cleansing” but also the words “massacre” and “genocide” were quickly applied to Serb operations. The remarkable inflation of claims of Serb evil and violence and playing down of NATO clients’ violence , with fabricated “concentration camps, ” “rape camps,” and similar Nazi- and Auschwitz-like analogies, caused the onetime head of the U.

Popular perceptions pertaining to the Bosnian Muslim government have been forged by a prolific propaganda machine. A strange combination of three major spin doctors, including public relations PR firms in the employ of the Bosniacs, media pundits, and sympathetic elements of the US State Department, have managed to manipulate illusions to further Muslim goals. But this claim came to grief in , when two different studies, the first sponsored by the ICTY itself and the other by the Norwegian government, concluded that the Bosnian conflicts had resulted in combined deaths on the order of one hundred thousand for all sides, including both civilians and military victims.

How Good Are Those Young-Earth Arguments?

Jena Verlag von Gustav Fischer. Bivalve paleogeography and the Hispanic corridor: Paleogeography, Paleoclimatology and Paleoecology,

U–Th dating of broken speleothems from Cacahuamilpa cave, Mexico: Are they recording past seismic events? U–Th dating on speleothems: a preliminary record of the cave’s lifetime. Although not directly the focus of this study, the obtained U-series disequilibrium ages are important for understanding the evolution of the Cacahuamilpa cave.

Godthelp in Hill, Robert S. White, , The Nature of Hidden Worlds: Australian Conservation Foundation, Melbourne. Michael Archer, Suzanne J. Gehling, Kathleen Grey, Guy M. Franklin, The revolution that didn’t arrive: Aboriginal History 9, Frith, Cape York Peninsula: A Natural History, Reed, D. Hobbs and Colin J. Marine Geology, 25, Australian Journal of Botan, 32, Transactions of the Royal Society of South Australia, ,

How Good Are Those Young-Earth Arguments?

By Andrew Jenner March 28, 1: Heinrich Frank It was in that Amilcar Adamy first investigated rumors of an impressive cave in southern Brazil. After asking around, he eventually found his way to a gaping hole on a wooded slope a few miles north of the Bolivian border. Those caves looked nothing like this large, round passage with a smooth floor. Heinrich Frank, a professor at the Federal University of Rio Grande do Sul, was zipping down the highway on a Friday afternoon when he passed a construction site in the town of Novo Hamburgo.

There, in a bank where excavators had eaten away half of a hill, he saw a peculiar hole.

-Open-system alpine speleothems: implications for U-series dating and paleoclimate reconstructions -The present work is a critical review of alpha-spectrometric U/Th analyses of speleothems.

Broken and damaged stalagmites were found in Cacahuamilpa cave, Mexico. Abstract Cacahuamilpa cave is one of the largest karst systems in Central Mexico. The cave contains numerous massive speleothems broken and fallen following oriented directions, damaged during cataclysmic geological events. One fallen and two broken speleothems were sampled in the Cacahuamilpa cave for dating the rupture event using measured U—Th disequilibrium ages. A total of eight small carbonate cores were drilled perpendicular and longitudinal to the rupture surface.

Results showed three groups of ages weighted average: This indicates that the construction of the Cacahuamilpa karst system, for which no absolute ages existed before this study, initiated at least since Late Pleistocene. The first two groups of ages might be related to two distinct episodes of intense seismic activity.

C14-datering

The Sahara desert is expanding; it can only be a few thousand years old. The present Sahara Desert really is only a few thousand years old. About 7 or 8 thousand years ago the area underwent a pronounced wet phase and portions of it were habitable parkland where cattle could be grazed The Times Atlas of World History, More than 10, years ago, during the last glaciation, lakes and streams were present in the Sahara, and elephants, giraffes, and other animals roamed the grasslands and forests which covered much of the region.

Not long ago radar was used to discover a fossil river which once flowed across the Sahara; the river bed is now buried beneath the desert sands.

U–Th dating of speleothems to investigate the evolution of limestone caves in the Gunung Mulu National Park, Sarawak, Malaysia. Gina E MOSELEY 1,2,3, David A RICHARDS 2,3, Christopher J M SMITH.

De mate waarin dit verval al is opgetreden, kan vervolgens worden gebruikt om te bepalen hoelang geleden het organisme is gestopt met het uitwisselen van 14C met zijn omgeving. Materiaal dat erg oud is bijvoorbeeld steenkool , zal daardoor vrijwel geen 14C meer bevatten. Met behulp van massaspectrometrie kunnen de relatieve gehaltes aan verschillende isotopen nauwkeurig worden bepaald. Het gehalte 14C in de atmosfeer is door de tijd niet constant gebleken. Er is ook nu nog geen evenwicht bereikt in de aanmaak en vergaan van C Waarom kalibratie noodzakelijk is[ bewerken ] Om deze paragraaf helemaal te begrijpen is het handig enige kennis van de koolstofcyclus te hebben.

Blombos Cave

Early Cretaceous polar faunas of Gondwana and Laurasia and their environmental setting are also emphasized – with studies involving fluvial sedimentology, palynology and stable isotope Geochemistry, the general morphology and microanatomy of bones and teeth and the physiological adaptation of the biota to high latitude, extreme environments. Other programmes examine the use of vertebrates in biostratigraphy especially in terrestrial sequences and the late impact of humans on the Australian megafauna.

Dinosaurs of Darkness By Thomas H. Rich and Patricia Vickers-Rich Book description Discover the lost world of the Antarctic dinosaurs and how its secrets have been unearthed. Dinosaurs of Darkness opens a doorway to a fascinating former world that existed in Australia between million and million years ago.

brief about, the cave locations, cave length, host rock condition, U-Th dating uncertainties and speleothems potential with14C AMS chronology. We had identified mostly the cave formed in Deoban limestone of Tejam Group. Among these caves, only four caves seem suitable due to .

Karst activity with contributions from A. Karst is a type of landscape found on carbonate rocks limestone, dolomite, marble or evaporites gypsum, anhydrite, rock salt and is typified by a suite of landforms including a wide range of closed surface depressions, a well-developed underground drainage system, and a paucity of surface streams. Karst in carbonate rocks is formed by their dissolution by acidic water. Most dissolution occurs when rainwater picks up carbon dioxide from the air, and decaying organic matter in the soil, becoming more acidic and then percolates through cracks dissolving the rock.

When the bedrock becomes saturated with water, dissolution continues as the water moves sideways along bedding planes horizontal cracks between rock layers and joints or fractures in the rock itself. These conduits enlarge over time, and move the water, via a combination of gravity and hydraulic pressure, further enlarging the conduits through a combination of dissolution and abrasion of the surrounding rock.

This is Geochronology – Pieter Vermeesch